A cognitive psychologist has developed a computer simulation of memory processes that generates a simulation of reaction times in response to the presentation of previously learned stimuli.The program has been designed to produce a mean reaction time of 200 msec with a standard deviation of 20.The psychologist is worried that the program has stopped working properly because the last 16 trials have produced a mean reaction time of 190 (with the expected standard deviation of 20).The researcher compares the two means using a z-test to ask whether the observed mean is lower than the expected mean.Which of the following statements is false?
A)A t-test could not be used on these data as the standard deviation is known.
B)A t-test could be used on these data even though the standard deviation is known but the z-test is the best option.
C)A t-test could be used on these data even though the standard deviation is known and it is a better option than the z-test because it can be done in SPSS.
D)A t-test could be used on these data but the z-test is the best option as it is simpler.
E)All of the above apart from (b).

Question

Quizplus · Accepted Answer

A t-test is typically used when the population standard deviation is unknown and the sample size is small. However, even when the population standard deviation is known, a t-test can still be used, especially when the sample size is small (less than 30). The choice of a z-test in this scenario is appropriate due to the known population standard deviation, but stating that a t-test could not be used or is a worse option simply because the standard deviation is known or because of software capabilities is incorrect. The simplicity of the z-test makes it a good option, but it doesn't invalidate the use of a t-test.

A Cognitive Psychologist Has Developed a Computer Simulation of Memory